Hepatitis A is a highly contagious liver infection caused by the hepatitis A virus. The virus is one of several types of hepatitis viruses that cause inflammation and affect your liver's ability to function.

You're most likely to contract hepatitis A from contaminated food or water or from close contact with someone who's infected. Mild cases of hepatitis A don't require treatment, and most people who are infected recover completely with no permanent liver damage.

Practicing good hygiene, including washing hands frequently, is one of the best ways to protect against hepatitis A. Vaccines are available for people most at risk.

Hepatitis A signs and symptoms, which typically don't appear until you've had the virus for a few weeks, may include:

Fatigue

Nausea and vomiting

Abdominal pain or discomfort, especially in the area of your liver on your right side beneath your lower ribs

Clay-colored bowel movements

Loss of appetite

Low-grade fever

Dark urine

Joint pain

Yellowing of the skin and eyes (jaundice)

If you have hepatitis A, you may have a mild illness that lasts a few weeks or a severe illness that lasts several months. Not everyone with hepatitis A develops signs or symptoms.

When to see a doctor

Make an appointment with your doctor if you have signs or symptoms of hepatitis A.

If you've been exposed to hepatitis A, having a hepatitis A vaccine or immunoglobulin therapy within two weeks of exposure may protect you from infection. Ask your doctor or your local health department about receiving the hepatitis A vaccine if:

You've traveled internationally recently, particularly to Mexico or South or Central America, or to areas with poor sanitation

A restaurant where you recently ate reports a hepatitis A outbreak

Someone close to you, such as someone you live with or your caregiver, is diagnosed with hepatitis A

You recently had sexual contact with someone who has hepatitis A

The hepatitis A virus, which causes the infection, usually is spread when a person ingests even tiny amounts of contaminated fecal matter. The hepatitis A virus infects liver cells and causes inflammation. The inflammation can impair liver function and cause other signs and symptoms of hepatitis A.

Hepatitis A virus can be transmitted several ways, such as:

Eating food handled by someone with the virus who doesn't thoroughly wash his or her hands after using the toilet

Drinking contaminated water

Eating raw shellfish from water polluted with sewage

Being in close contact with a person who's infected — even if that person has no signs or symptoms

Having sex with someone who has the virus

You're at increased risk of hepatitis A if you:

Travel or work in regions with high rates of hepatitis A

Attend child care or work in a child care center

Are a man who has sexual contact with other men

Are HIV positive

Have a clotting-factor disorder, such as hemophilia

Use injected or noninjected illicit drugs

Live with another person who has hepatitis A

Have oral-anal contact with someone who has hepatitis A

Unlike other types of viral hepatitis, hepatitis A does not cause long-term liver damage, and it doesn't become chronic.

In rare cases, hepatitis A can cause loss of liver function that occurs suddenly, especially in older adults or people with chronic liver diseases. Acute liver failure requires hospitalization for monitoring and treatment. Some people with acute liver failure may require a liver transplant.

If someone close to you is diagnosed with hepatitis A, ask your doctor or local health department if you should have the hepatitis A vaccine to prevent infection.

If you have signs and symptoms of hepatitis A, make an appointment with your family doctor or a general practitioner.

What you can do

Because appointments can be brief and there's often a lot of ground to cover, it's a good idea to be well-prepared.

Be aware of pre-appointment restrictions. When you make the appointment, find out if there's anything you need to do in advance, such as restrict your diet.

Write down your symptoms, including any that seem unrelated to the reason for your appointment.

Write down key personal information, including major stresses or recent life changes.

List medications, vitamins and supplements you take.

Consider taking a family member or friend along. Someone who accompanies you may remember something that you missed or forgot.

Write down questions to ask your doctor.

Listing questions for your doctor can help you make the most of your time together. For hepatitis A infection, some basic questions to ask your doctor include:

What is likely causing my symptoms or condition?

Other than the most likely cause, what are other possible causes for my symptoms or condition?

If I have hepatitis A, what can I do to keep from infecting others?

Should people close to me receive the hepatitis A vaccine?

Can I continue to work or go to school while I have hepatitis A?

What signs and symptoms signal that my hepatitis A is causing serious complications?

How will I know when I can no longer pass hepatitis A to others?

Are there brochures or other printed material I can have? What websites do you recommend?

Don't hesitate to ask other questions you have.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, including:

When did your symptoms begin?

Have your symptoms been continuous or occasional?

How severe are your symptoms?

What, if anything, seems to improve your symptoms?

What, if anything, appears to worsen your symptoms?

Blood tests are used to detect the presence of hepatitis A in your body. A sample of blood is taken, usually from a vein in your arm, and sent to a laboratory for testing.

No specific treatment exists for hepatitis A. Your body will clear the hepatitis A virus on its own. In most cases of hepatitis A, the liver heals within six months with no lasting damage.

Hepatitis A treatment usually focuses on coping with your signs and symptoms. You may need to:

Rest. Many people with hepatitis A infection feel tired and sick and have less energy.

Cope with nausea. Nausea can make it difficult to eat. Try snacking throughout the day rather than eating full meals. To get enough calories, eat more high-calorie foods. For instance, drink fruit juice or milk rather than water.

You can take steps to reduce the risk of passing hepatitis A to others.

Avoid sexual activity. Avoid all sexual activity if you have hepatitis A, since many kinds of sexual activity can expose your partner to infection. Condoms don't offer adequate protection.

Wash your hands thoroughly after using the toilet. Scrub vigorously for at least 20 seconds and rinse well. Dry your hands with a disposable towel.

Don't prepare food for others while you're actively infected. You can easily pass the infection to others.

The hepatitis A vaccine can prevent infection with the virus. The hepatitis A vaccine is typically given in two doses — initial vaccination followed by a booster shot six months later.

The Centers for Disease Control and Prevention recommends the following individuals receive a hepatitis A vaccine:

All children at age 1, or older children who didn't receive the vaccine at age 1

Laboratory workers who may come in contact with hepatitis A

Men who have sex with men

People planning travel to areas of the world with high rates of hepatitis A

People who use illegal drugs, injected and noninjected

People who receive treatment with clotting-factor concentrates

People with chronic liver disease

If you're concerned about your risk of hepatitis A, ask your doctor if you should be vaccinated.

Follow safety precautions when traveling

If you're traveling in regions where hepatitis A outbreaks occur, peel and wash all fresh fruits and vegetables yourself and avoid raw or undercooked meat and fish. Drink bottled water and use it when brushing your teeth. Don't drink beverages of unknown purity, with or without ice. If bottled water isn't available, boil tap water before drinking it.

Practice good hygiene

Thoroughly wash your hands often, especially after using the toilet or changing a diaper and before preparing food or eating.

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